1. Field of the lnvention
This invention relates to the art of laser welding and more particularly to a method of laser welding an electrically conductive material, such as an electrical lead, to an electrically conductive layer which has been adhered to and which overlies a curved non-metallic substrate.
2. History of the Prior Art
Welding or connecting aluminum foil leads to aluminum coated non-metallic, curved substrates has previously been accomplished by utilizing several mechanical welding or soldering techniques. One of these techniques has been the utilization of an ultrasonic mechanical bonding technique which comprises placing very small welding points on the materials to be bonded together. During this process twenty to thirty welding points are needed in order to make a bond. This technique has not been reliable in either strength or endurance. New methods were sought which would produce a strong and durable bond. ln order to produce strong and durable welding bonds, there must be good contact between the materials to be bonded during the bonding process. This is particularly difficult when one of the materials has a curved surface as in the instant invention and the substrate containing one of the materials thereon, is non-metallic.